Prefer get_user_config_dir over get_home_dir for finding the panel config dir
For example: `whiskermenu_path = os.path.join(GLib.get_home_dir(), '.config/xfce4/panel/', whiskermenu_file)` `whiskermenu_path = os.path.join(GLib.get_user_config_dir(), 'xfce4/panel/', whiskermenu_file)`
issue